As the hero rides into the sunset, the screen 'fades to black'. [=the image gradually changes until the screen is completely black]
His voice 'faded' off into a whisper. = His voice 'faded' to a whisper.
We watched the ship gradually 'fade' from view as it sailed away.
(..) Out! - Magic comes at a lofty price. - And the expense grows. - You look... - Old. - Tired. My power fades. I have something for what ills you. Greta? Greta?! Mirror, mirror, on the wall. Who is fairest of them all? (..)2012 Snow White and the Huntsman